A culture of MPs "who have to put their party first" is prompting Brendan Horan to start a new political party - one made up of independent MPs.

The announcement came at the same time as Horan said the executor's final determination on whether he took money from his late mother's accounts had cleared him of any wrongdoing.

Horan became an independent MP after being expelled from NZ First in 2012 amid allegations he illegally took money from his late mother, Olwen Horan.

"There was never any wrongdoing, and from the start I said that," Horan said today.

"I've been in a position where there was no due process and I was consistently and maliciously defamed over the past year and my reputation's sullied.

"I'm sick of it. It was complete rubbish; it always was and people should have checked their sources."

But sources who have seen executor John Buckthought's final determination believe it does not "clear" Horan.

It states that money is being eaten up by legal fees and the estate should be settled in the interests of the beneficiaries.

Horan's lawyer, Paul Mabey, QC, has denied reports that a settlement of the estate took place to save money.

It is understood a settlement was reached because Buckthought decided enough money had been spent on legal fees and a forensic investigation, and the estate should be settled before it was wiped out.

Fairfax Media understands more than $100,000 had been spent on the forensic investigation and lawyers, including fees to defend an unsuccessful court action by Horan aimed at having Buckthought removed as executor.

Horan did not rule out taking defamation action against some parties, saying the matter was with his lawyers.

"People seem to forget it was my mum that died," he said.

"I have young children and nieces who are so hurt by the foul and vile claims and false accusations."

At the time, NZ First leader Winston Peters told Parliament that Horan had been expelled from the party after he received "substantive information" that meant he no longer had confidence in Horan.

Horan said today that through his work as an independent in Parliament he had seen disenchanted MPs who were not able to serve their communities properly.

"It's become clear to me there are a lot of disgruntled MPs in Parliament who would love to vote for the people of their area but can't because they have to put their party first," he said.

A political party made up of independent MPs would "change the system" and make MPs "truly accountable and transparent".

"So essentially what would happen is there would still be a party insofar there's a party entity," Horan said.

"For governance, we'd agree on confidence and supply, but on votes in Parliament, MPs would vote on what's best for their area."

He said work was being done to register the New Zealand Independent Coalition as a party, and expressions of interest were coming in from people wanting to stand.

Anybody would be free to join, even if they were involved with other parties.

"But to become a candidate, we would adopt the process JPs have to go through at the moment, where they need to be recommended by at least two community organisations, because we want MPs who are involved in their communities and can actually demonstrate it," Horan said.